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Periodontal disease (PD) has been suggested to be a risk factor for Alzheimer’s disease (AD). We tested the impact of ligature-induced PD on 5xFAD mice and WT littermates. At baseline, 5xFAD mice presented significant alveolar bone loss compared to WT mice. After the induction of PD, both WT and 5xFAD mice experienced alveolar bone loss. PD increased the level of Iba1-immunostained microglia in WT mice. In 5xFAD mice, PD increased the level of insoluble Aβ42. The increased level in Iba1 immunostaining that parallels the accumulation of Aβ in 5xFAD mice was not affected by PD except for a decrease in the dentate gyrus. Analysis of double-label fluorescent images showed a decline in Iba1 in the proximity of Aβ plaques in 5xFAD mice with PD compared to those without PD suggesting a PD-induced decrease in plaque-associated microglia (PAM). PD reduced IL-6, MCP-1, GM-CSF, and IFN-γ in brains of WT mice and reduced IL-10 in 5xFAD mice. The data demonstrated that PD increases neuroinflammation in WT mice and disrupts the neuroinflammatory response in 5xFAD mice and suggest that microglia is central to the association between PD and AD.

This study compares the gait of chronic ambulatory hemiplegic elderly (HE) with those of non-hemiplegic elderly (NHE) using Vicon® 512 motion analysis system to track movement trajectories. Subjects walked with self-selected gait speeds while temporal, spatial, and kinematic variables were analyzed. HE showed significantly decreased walking speed, cadence, stride length, and step length, and increased stride time, step time, and double limb support periods in comparison with NHE. Double limb support of stance phase was significantly increased in HE. In HE, affected pelvis showed marked upward elevation from terminal stance to mid swing phase, and greater external rotation than the NHE (p

We studied newly developed assistive robot movement (ARM, HEXAR-KR40P) equipment, and compared with conventional continuous passive movement (CPM) equipment, focusing on range of motion (ROM) and strengthening of knee joint muscles. 110 osteoarthritis (OA) patients were recruited from five different clinics. At first, eighty patients were enrolled to evaluate the subjective satisfaction of ARM. Secondly, thirty patients were enrolled to find the effectiveness of ARM including ROM and strength compared with CPM. Subjects in first study performed exercise for two weeks. Exercise was performed with CPM and ARM for ten minutes alternately. Subjects in second study performed exercise with ARM only 30 min/day for two weeks, and measured ROM, strength, and functional changes. Obtained data was analyzed with Wilcoxon signed rank test. As a result, higher subjective satisfaction with ARM in patients and researchers survey was noted compared with CPM (p

Honokiol, a neolignan, is a physiologically active component of kouboku (Magnolia obovata), a herb used in traditional Chinese medicine. This study investigated the effects of honokiol on the differentiation and function of osteoclasts induced by receptor activator of nuclear factor-kappaB ligand (RANKL). Honokiol markedly inhibited RANKL-induced tartrate-resistant acid phosphatase (TRAP) activity and the formation of TRAP-positive multinucleated cells in both bone marrow-derived monocytes and RAW264 cells. In experiments to elucidate its mechanism of action, honokiol was found to suppress RANKL-induced phosphorylation of p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). The RANKL-induced expressions of c-Fos and nuclear factor of activated T cells-c1 (NFATc1), which are crucial transcriptional factors for osteoclastogenesis, were also reduced by treatment with honokiol. Furthermore, honokiol induced disruption of the actin rings in mature osteoclasts (mOCs) without affecting the cell viability and suppressed osteoclastic pit formation on dentin slices. Taken together, these results suggest that honokiol inhibits osteoclast differentiation by suppressing the activation of MAPKs (p38 MAPK, ERK and JNK), decreasing the expressions of c-Fos and NFATc1, and attenuates bone resorption by disrupting the actin rings in mOCs. Therefore, honokiol could prove useful for the treatment of bone diseases associated with excessive bone resorption.

We reported 8 to 13 years of follow-up of cases of tuberculosis of the hip previously. Now we report on 60 cases of hip tuberculosis treated with total hip arthroplasty. The results have been reasonably acceptable, with the longest follow-up >28 years. Prosthetic life was limited to at most 20 years in our longest cases mainly because of loss of fixation of the acetabular component. There were recurrences of tuberculosis in 5 hips. We confirmed that antituberculous chemotherapy is crucial in total hip arthroplasty reconstruction. Detection of Mycobacterium tuberculosis using polymerase chain reaction may provide rapid diagnosis and follow-up for treatment response.

Osteoclasts are multinucleated cells that play a crucial role in bone resorption, and are formed by the fusion of mononuclear osteoclasts derived from osteoclast precursors of the macrophage lineage. Compounds that specifically target functional osteoclasts would be ideal candidates for anti-resorptive agents for clinical applications. In the present study, we investigated the effects of luteolin, a flavonoid, on the regulation of receptor activator of nuclear factor-kappaB ligand (RANKL)-induced osteoclastogenesis, functions and signaling pathway. Addition of luteolin to a coculture system of mouse bone marrow cells and ST2 cells in the presence of 10(-8) M 1alpha,25(OH)(2)D(3) caused significant inhibition of osteoclastogenesis. Luteolin had no effects on the 1alpha,25(OH)(2)D(3)-induced expressions of RANKL, osteoprotegerin and macrophage colony-stimulating factor mRNAs. Next, we examined the direct effects of luteolin on osteoclast precursors using bone marrow macrophages and RAW264.7 cells. Luteolin completely inhibited RANKL-induced osteoclast formation. Moreover, luteolin inhibited the bone resorption by mature osteoclasts accompanied by the disruption of their actin rings, and these effects were reversely induced by the disruption of the actin rings in mature osteoclasts. Finally, we found that luteolin inhibited RANKL-induced osteoclastogenesis through the suppression of ATF2, downstream of p38 MAPK and nuclear factor of activated T-cells, cytoplasmic, calcineurin-dependent 1 (NFATc1) expression, respectively. Taken together, the present results indicate that naturally occurring luteolin has inhibitory activities toward both osteoclast differentiation and functions through inhibition of RANKL-induced signaling pathway as well as actin ring disruption, respectively.

Organotin compounds, such as tributyltin (TBT) and triphenyltin (TPT), have been widely used in agriculture and industry. Although these compounds are known to have many toxic effects, including endocrine-disrupting effects, their effects on bone resorption are unknown. In this study, we investigated the effects of organotin compounds, such as monobutyltin (MBT), dibutyltin (DBT), TBT, and TPT, on osteoclast differentiation using mouse monocytic RAW264.7 cells. MBT and DBT had no effects, whereas TBT and TPT dose-dependently inhibited osteoclast differentiation at concentrations of 3-30 nM. Treatment with a retinoic acid receptor (RAR)-specific antagonist, Ro41-5253, restored the inhibition of osteoclastogenesis by TBT and TPT. TBT and TPT reduced receptor activator of nuclear factor-kappaB ligand (RANKL) induced nuclear factor of activated T cells (NFAT) c1 expression, and the reduction in NFATc1 expression was recovered by Ro41-5253. Our results suggest that TBT and TPT suppress osteoclastogenesis by inhibiting RANKL-induced NFATc1 expression via an RAR-dependent signaling pathway.

Study Design. The biomechanical role of transfixation in pedicle screw instrumentation was investigated using flexibility tests and finite element analyses. Objective. To assess the stabilizing effect of use and position of transfixators. Summary of Background Data. Transfixation is common in pedicle screw instrumentation, however, its biomechanical role and optimal position are not completely understood. Methods. Specimens underwent nondestructive flexibility tests using a three-dimensional motion analysis system. Tests compared the intact spine with instrumentation with and without transfixators. Rotational angles of the superior vertebra, resulting from the maximum moment of 6.4 Nm, were compared. Three-dimensional finite element models investigated transfixator position. Rotations of the superior vertebra were compared for cases with and without transfixators to determine the position providing the greatest stability. Results. Biomechanical test showed that only axial rotational stability significantly improved with transfixators compared with instrumentation alone. Finite element models predicted improvement in lateral bending and axial rotation with transfixators compared with the case with no transfixator. With one transfixator, the greatest improvement in axial rotation stability occurred with the transfixator at the proximal 1/4 position of the rods. When two transfixators were used, the optimal locations were with one transfixator in the middle and the second at the proximal 1/8 position. Conclusions. Transfixators improved the stabilizing effects of pedicle screw instrumentation. The greatest axial rotation stability was obtained with two transfixators; one in the middle and the other at the proximal 1/8 position of the longitudinal rods.

Purpose : To confirm the effect of the frog leg lateral radiographs for determining the clinical indication of total hip arthroplasty for high riding dislocation and to discuss its theoretical background. Materials and Methods : A consequent series of reconstructive THA were studied in 28 recent tuberculous hips. Twenty-three hips (17 patients) with developmental dysplastic hip were compared. Preoperatively, frog-leg lateral radiographs were performed in all the patients, which were enhanced using a 2-dimensional computer model to predict the reattachment of the greater trochanter. Results : The modified scores of Merle d'aubigne and Postel improved from a mean of 2.6 points preoperatively to a mean of 5.1 points. Sciatic nerve palsies occurred in three cases. In two cases, they fully recovered, but in one case, it did not. We confirmed that old high dislocation of the hip could be adopted in type 1 and 2 categories of frog leg lateral position. The reconstruction of hip was relatively simple in type 3, however, further study is necessary in type 5 due to unsuitable abduction contracture. Conclusion : We confirm that frog leg lateral radiography is effective for determining the operative indication of high riding dislocation. However irreducible frog leg lateral position is absolutely contraindirated for total hip arthroplasty.

Purpose : To observe dystrophin formation and histological improvement in dystrophic muscle of mdx mouse after normal myoblast injection. Materials and Methods : Cultured myoblasts from genetically normal rats were injected into the right quadriceps femoris of a 6-week-old mdx mouse (n=9). dPBS was injected into the left quadriceps femoris as a control. One, 2, and 3 months after injection, The control and experimental group were compared histologically and by dystrophin immunostaining. Results : When compared with controls 3 months postoperatively, quadriceps femoris in the experimental group exhibited greater cross-sectional area and total fiber number, and the experimental animals contained more normal-appearing and less abnormalappearing fibers than the control group. Most of the fibers in the experimental group showed positive results in dystrophin immunostaining, whereas immunostaining of mdx muscle fibers in the control group was completely negative. Conclusion : This study shows that normal myoblast injection improved the muscle architecture histologically and produced dystrophin protein in dystrophic muscle.

We report 60 patients with tuberculosis of the hip treated by Charnley low friction arthroplasty and followed for eight to 13 years. Eight of them had active tuberculosis of the hip at the time of operation, and all were covered by relatively short courses of antituberculous drugs. Our study suggests that arthroplasty can be recommended for these patients provided that adequate chemotherapy is given both before and after operation.